A036934 Smallest n-digit prime containing only digits 1 and 7, or 0 if no such prime exists.

7, 11, 0, 1117, 11117, 0, 1111711, 11111117, 0, 1111117171, 11111111771, 0, 1111111111177, 11111111171177, 0, 1111111111171177, 11111111111111171, 0, 1111111111111111111, 11111111111111117111, 0, 1111111111111111111711

Offset: 1

Author

Patrick De Geest, Jan 04 1999

Keywords

• nonn
• base

Links

• Jinyuan Wang, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A020455, A036307, A036229.

Programs

Mathematica

Flatten[Table[Select[FromDigits/@Tuples[{1, 7}, n], PrimeQ, 1], {n, 25}]/.{}->{0}] (* Jinyuan Wang, Mar 09 2020 *)

Extensions

a(16) corrected by Jinyuan Wang, Mar 09 2020